Electric furnace and operating mechanism therefor



Aug. 7, 1928. 1,680,237

S. ARNOLD, 3D

ELECTRIC FURNACE AND OPERATING MECHANISM THEREFOR Filed March 23, 1926 4 Sheets-Sheet 1 INVENTOR Aug. 7, 192 8.

5. ARNOLD, 3D

ELECTRIC FURNACE AND OPERATING MECHANISM THEREFOR 4 Sheets-Sheet Filed March 23, 1926 INVENTOR MN mi. N N M Aug. 7, 1928. 1,680,237

S. ARNOLD, 8D

ELECTRIC FURNACE AND OPERATING MECHANISM I 'HEREFOR Filed March 23, 1926 4 Sheets-Sheet 3 Aug. 7, 1928. 1,680,237

S. ARNOLD, 3D

ELECTRIC FURNACE AND OPERATING MECHANISM THEREFOR Filed March 23, 1926 4 Sheets-Sheet 4 INVENTOR ,mma'i .1,'1 i8. 1,680,237 y UNITED STATES PATENT OFFICE.

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The present invention relates broadl to the art of'fnrnaces, and more particular y to electric furnaces and improved operating j means for the same. 1

b At the present'time it is customary in the art to which my invention relates to construct electric furnaces in a number of different ways, the of cases being so mounted as to permit tilting of the molten metal from the furnaces. With melting furnaces of the larger capacity, the tilting has usually been accomplished by lifting the furnaces from below in some suitable manner, such as by a crank, screw or hydraulic cylinder. I In some cases the tilting has taken place about a fixed axis, while in other cases the axis has been of the gradually shifting type such as provided by rock: ing the furnace either by means of mechanism placed entirel below the furnace, or by mechanism on the urnace platform or at the sides of the furnace.

The use of a shifting axis is objectionable by reason of the consequent forward travel imparted to the discharge spout, thereby resulting in a changing point of impingement of the molten metal in the receptacle, such as a ladle, provided 'for it. This change has" 80 notinfrequently been sufficient to necessitate adjustment of the ladle during the tapping operation. This same objection, but to a less degree, is inherent in furnaces having a fixed axis in which the discharge spout is at a considerable distance from such axis. of the objects to provide a tilting furnace in which the point of impingement of the molten metal is maintained more nearly constant. In many cases, with operating mechanism of the general character referred to, there has beena pit provided beneath the furnace.

not only ,to accommodate the furnace itself, but also its supporting and operating mechanism. Mechanism so located is objectionable due to the liklihood of damage or imperfect operation byl reason of the presence or accumulation of ot metal, slag, dirt and the like. Also, the pit represents a hazard at all times due to the possibility of the presonce of water therein which ma result in a serious explosion in the event 0 the spilling of molten metal into the same or to the failure of a furnace bottom. J 1

' Another object of the present invention is to provide improved operating mechanism furnaces in a large number.

or rocking thereof to facilitate the discharge I It is one,

,nace,it may have so located as not to only obviate the necessity of a pit or its uivalent, but also as-to preclude the possibi 'ty of interference from the causes re erred 'to. These advantages are conveniently accomplished by locating the o crating mechanism entirely above the p ane of the furnace, whereby access to ,the furnace isexpedited and its-operation ren dered easier andsafer.

Another object of this invention is to provide a furnaceinstallation requiring a minimum of power for each tiltin operation, the furnace preferably being entirely or partial? 1y connterweighte?! whereby the operating inecihanism is reli ved of a corresponding In the accompanyin drawings these are shown for purposes of illustration only, certain preferred embodiments of the present invention, it being understood that the drawings do not define the limits of my invention disclosed therein may be made without departing either from the spirit of'my inventionor the scope of my broader claims.

In the drawings:

Figure 1 is a side elevational view, largely diagrammatic, of one form of furnace instal: lation in accordance with the present inven-' tion;

Figure 2 is a top plan view of the arrangement of Figure 1 Figure 3 is a view, similar to Figure 1, illustrating a modified embodiment of the invention;

Figure 4 is a top plan view of the modification of Figure 3;

Figure 5 is a vertical sectional view on the line V-V of Figure 3, looking in the direc-' tion of the arrows, and j Figure 6 is a detail view, scale, of as shown in Figure '3;

In carrying out the present invention, there may be provided a furnace 2 of any desired construction having a charging spout 3 and a discharge spout 4.. To provide a tilting support of the fixed axis type for the furformed thereon bearings 5, conveniently located on opposite sides of the discharge spout, and adapted to receive a horizontall extending shaft or trunnion 6, supported in bearing standards 7.. By reason of this construction, it will be obvious that the tilting axis is located adjacent the spout, thereby enabling on an enlarged the discharging ofas changes in the construction and operation the furnace to be accomplished with a total travel of the spoutthrough a comparatively short are and with a minimumof-lateral shifting.

' mally Located adjacent one side of the furnace,

-and preferably opposite the discharge-spout 4, is an elevated platform 8, the platform preferably being of such height as'to norlie entirely above the body of the furnace 2. Mounted on the platform adjacent each of the two corners nearest the furnace is a series of guiding sheaves 9 and a second series of similar sheaves 10 of any desired construction. Adjacent each of the other corners of the latform is another series of sheaves 11. lassing around the sheaves 9 and 11, are cables 12, these cables being preferably arranged in pairs, with each pair connected at one end to a counterweight 13, and at the other end to suitableoints 14 011 the sub frame 15 of the furnace. assing over the sheaves 10 are cables 16, these cables being connected at one end to the oints'14 on the furnace sub frame, and at tlib other end passing around cable drums 17. These drums are conveniently secured adjacent the opposite ends of a shaft 18 carried in bearings 19 on the platform and driven in either direction at will byany suitable means, such as a motor 20 and a reduction gearing of suitable type, not shown,

mounted within a protective casing 21.

The counterweights 13 may have a combined effective weight slightly less than that of the furnace 2, whereby the furnace is substantially counterbalanced while having suflicient difference in weight in favor of the furnace to insure the return of the furnace by gravity from its dotted line discharging positionof Figure 1 to its normal full line osition when the motor 20 is operated in the proper direction to permit such a movement thereof. In this manner the power required to tilt the furnace is kept at a minimum, enabling not only an easy tilting operation but a very smooth and gradual change in inclination whereby comparatively'small amounts of metal may be easily discharged even from a large capa c-i ity furnace without any danger of spilling or splashing the metal. The platform may be so constructed and supported as to permit free access to the furnace, and normal operationof the charging spout 3 while supporting all of the operating mechanism in a safe place from the standpoint, both of the operatives engaged in working or superintending the working of. the furnace and from that of comparative immunity" from interference by molten metal or other foreign material. In additional, the platform provides convenient means for supporting a counterweight mechanism for the furnace. It will thus be seen .that there is provided a furnace which may be safely and easily operated with a minimum of power, without the necessity of a pit or operating mechanism below the furnace and without obstructing free access to and operation of the furnace.

In Fi disclose the invention, operating, however, on the same general principle as that heretofore described. The furnace 2 is provided with a mounting 6, permitting tiltin thereof in the manner set forth. At the side of the furnace opposite the pivotal mounting there is provided a suitable frame structure 22, carrying a platform 23 at a substantial distance above the plane of the furnace. Below the 24 carrying a shaft 25 on which is mounted any desired number of sheaves 26 for guidin cables 27 each connected at one end to a suitable point 28 on the sub frame 29 of the furnace and at the opposite end to a counterweight 30. As illustrated more particularly in Figure 5 of the drawings, there may be provided two of the counterweights, one being located adjacent each side of the supporting frame. In this. manner there is no interference with the free movement of the charging spout 31.

It being understood that the counterweights may be effective for counterbalancing the furnace to any desired degree, and even the furnace and its contents should this be desirable, as it might in some cases be desirable or necessary to positively move the furinace in both directions. If the furnace an balanced, the power required ures 3 to 6 of the drawings, there is for tilting the furnace will be substantially represented by the friction of the moving parts during the tilting operation, and the slight amount of additional power during the returning movement of the furnace as required to lift that portion of the counterweights previously effective for counterbalancing the charge formerly in the furnace: In any case, the power requirements are comparatively small and may easily be satisfied by the'provision of a motor 32 ona platform 23, connected by a suitable gear train 33 to a shaft 34. This shaft may have secured to each of its opposite ends adriving pinion 35 meshing with the combined gear and nut 36, the hub portion -of each of the gears forming a nut threaded internally to receive the screw shafts 37. Each of these screw shafts may be threaded throughout the required portion of the length and lower end, as indicated for example in Figure 3, to provide eyes 38 for the reception of pins 39 in the sub frame 29, thereby providing pivotal connections between the screw shafts and the furnace structure. It will be apparent that as the furnace is moved from the full line position of Figure 3 to a slightly modified embodiment of latform there are provided hangers its contents are completely counterformed at the 1 the dotted line position of this re, the travel in the arcs di circles, the screw shaft to depart a slight amount from a true vertical position. By reason of this movement, provision must be made to permit a corresponding movement of the combined gears an nuts 36. This may be accomplished, as illustrated in detail in Figure 6 of the drawings, by providing a pivotal support intermediate the hubs of the gears and the platform 23.

With a construction of the character just. described, operation of the motor 32 in one direction Wlll be effective for. aising the furnace to discharging positio Wltll a gradual movement enabling the discharging of any desired amount of the molten metal therefrom, while operation of the motor in the reverse direction will result in gradually lowering the furnace. The screw shafts not only provide a positive lock which holds the, furnace in any position tov which itmay be moved, but enables the furnace to be positively moved in both directions whereby the pins 39 will thereby causing effectiveness of the counterweight is not and/or its charge to any nism positioned above the limited as necessitated where gravity is relied upon to accomplish the return movement of the furnace.

In both embodiments of the invention there is provided operating mechanism obviating the necessity of any pits or the like, together with operating mechanism or supporting mechanism below the furnace, the support for the furnace being at one side thereof and above thebottom, and the operating mechanism being at a substantial distance above the floor line and preferably also above the plane of the furnace. This constitutes one of the advantages of the present invention.

Another advantage of the invention arises from the provision of an elevated platform having supporting means of such nature as to provide free access to, and an easy operation of the furnace without the possibility of danger to the furnace operatives by reason of the operating mechanism provi ed.

Still another advantage of thejinvention arises from the provision of a tilting furnace of such nature that the change laterally in the point of pour is reduced mum, as well as from the provision of means effective for counterbalancing the furnace desired extent, either completely, partially or toan excess.

I claim:

1. In a furnace installation, an electric furnace having a pivotal mounting above the bottom thereof, and operating mechaplane of the furnace and entirely at one-side thereoffor tilt ing the same about said mounting.

2. In an electric furnace installation; a furnace having a charging spout and a dis- -p ane of the to a mini charge spout,api votal moun 'g' for said furnace adjacent said dischargg spout, an operatin platform for sald. mace supported u on said platform for efiectmg ment of said. furnace.

3. In an electric furnace installation, a furnace, a pivotal mounting forsaid furnace entirel at one side thereof, operating mechanism or said furnace entirely atthe opposite side thereof, and means effective for counterbalancing said furnace to, the extent desired.

"4. In-an electric furnace installation, a furnace having a pivotal mountingfand operating mechanism op osite said mounting and above the plane of t e furnace for effecting movement of the mounting. 5. In an electricfurnace having ,a mounting permitting tilting movement thereof, and operating mechanism entirel at one side-ofv the furnace and above thep ane of the same for tilting the furnace.

6. In an tilting move-' .0 crating mechanism positioned abovethe furnace for effecting movement thereof, and means co-operating with the furnace for to the desired extent.

7. Operating mechanism for an electric furnace, comprising a supporting frame projecting above the normal plane of a furnace entirely laterally of the furnace, on said frame, and operatingmeans furnace located on said platform.

8. Operating mechanism for an electric furnace, comprising a jecting above the normal plane of a furnace entirely laterally of the furnace, on said frame, and operating means for a furnace located on said platform, said frame being provided with counterbalancing means for a furnace.

for a ovethe charging spout, and means,

furnace about saida platform supporting frame proelectric furnace installation, a furnace having a mounting permitting move-v ment for discharging the furnace contents,

counterbalancing the same a platform ositioned entirely above the normal floor ine, a pivotal support for said furnace on one side of the center line thereof, and operating mechanism for moving said furnace, said mechanism being located entirely above the floor line and entirely at the side of the furnace opposite said ivotal support. 10. In a furnace installation, an electric furnace having a pivotal mounting above the bottom thereof and on one side of the center, and operating mechanism for mov- I ing said furnace, said mechanism being" located entirely above said floor line and on the opposite side of said center.

11. In a furnace installation, a furnace mounting entirely "above afloor line, a

nace earned thereby entirely above the floor fur v 10 above the plane above the floor line and of the furnace, and fur-.

mounting entirely above a floor line, a furnace carried thereby entirely above the floor line, a platform above the floor line and entirely laterally of the furnace, and furnace tilting means on said platform, said furnace having a charging spout below said platform. I

In testimony whereof I have hereunto set my hand.

SAMUEL ARNOLD, 3m). 7 

